New Knee Implant Allows Patients to Keep Crucial Ligament

“The point of the
surgery is to
maintain as much
of the natural
knee as possible,” Dr. Humbert says.

For patients who need knee replacement surgery, gaining
the ability to move better means the loss of the anterior
cruciate ligament (ACL). Physicians have to cut the
ligament to get the new knee into place.

Orthopedic surgeon Edward Humbert, D.O., is among a
handful of physicians in the world who is working with a
new knee design—one that preserves the ACL.

“Inserting this artificial joint into the knee is technically
more challenging,” Dr. Humbert says. “But when it’s done
correctly, it feels like a natural knee.”

The point of the surgery is to maintain as much of
the natural knee as possible, Dr. Humbert says. “This
is a stable knee,” he says. “Is it better than the knee
replacements now, where we cut the ACL? Whether it’s
better or not is hard to predict.”

Two main advantages to the new design are stability and
proprioception—awareness of equilibrium. “This knee
feels as good as it possibly can,” Dr. Humbert says. “Even
so, when I explain it to many patients, because the style of
knee we’ve done for years still works very well, they do not
want to risk a new design.”

Dr. Humbert has implanted the new knee in several
patients who have had success in their recovery. “The
major advantage to this new design is that it maximizes
stability by maintaining the ACL and should mechanically
function like the natural knee—unlike all other total knee
designs,” he says. “It’s FDA (United States Food and Drug
Administration) approved but needs some longer follow-
up to determine which patients would benefit most with
new ACL-sparing total knee.”

Dr. Humbert implanted the new design in Shirley Alling’s
right knee earlier this year. The Pine Island resident had
been living with severe pain for more than a year. “My big
question going into surgery was, ‘Can I over exercise this
knee?’” Shirley says. “The answer was, ‘Absolutely not.’”

Just a few weeks after she completed surgery and follow-
up therapy, Shirley was back to her regular activities. “It’s
wonderful,” she says. “I’m walking now with no pain and
no limp.”

Dr. Humbert
learned the
technique
through
extended
orthopedic
training that
required
specialized
instruction
and rigorous
testing. He
has used
the knee in
approximately 2-3 patients per week but visualizes a time
when his patients demand more of the new design. “As
more people see that this functions like a real knee and is
cruciate preserving, they will ask for it.”